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updated canopy cover of 35.8%. The USGS Region 2 Regression Equations were used with an updated <br />canopy cover of 35.8% (instead of 52.7%), which yielded the peak flow results provided in Table 4.1. It is <br />anticipated that over the lifespan of the structure, canopy cover will re-establish. The 2017 aerial image <br />provided a conservative estimate for canopy cover (taken shortly after the Jolly Mountain Fire), though <br />there is potential for future fires, thus adding to the uncertainty of contributing hydrology to the project <br />site. <br />As mentioned in past studies technical memorandums at the Lick Creek project site (NHC, 2019), it <br />should be noted that there is large uncertainty in the hydrology, as shown by the standard errors of <br />prediction in Table 4.1. However, without a basin hydrologic model and available streamgage, the USGS <br />Regression Equations provide the best available information to be used for hydraulic modeling. Because <br />the proposed structure should be designed to be resilient for future changes within the basin, NHC <br />performed several sensitivity analyses, including the evaluation of various peak flow values using the <br />hydraulic model (Section 5.1.3). Based on the model results and through discussion with KCPW, it was <br />determined to utilize the updated 2017 canopy cover peak flow values (bold values in Table 4.1) for the <br />proposed structure's design (Sections 6 through 10). <br />Table 4.1 Peak Flows for Lick Creek at the NF Teanaway Road Crossing <br />2 -Year <br />68 <br />73 <br />77.2 <br />10 -Year <br />141 <br />194 <br />72.2 <br />25 -Year <br />187 <br />281 <br />81.2 <br />50 -Year <br />227 <br />361 <br />89.2 <br />100 -Year <br />268 <br />448 <br />96.9 <br />500 -Year <br />377 <br />699 <br />119.6 <br />North Fork Teanaway Road — Lick Creek Fish Passage Enhancement Project 21 <br />Hydraulics Basis of Design <br />